Sequencing and Comparative Genome Analysis of Two Pathogenic Streptococcus gallolyticus Subspecies: Genome Plasticity, Adaptation and Virulence

Streptococcus gallolyticus infections in humans are often associated with bacteremia, infective endocarditis and colon cancers. The disease manifestations are different depending on the subspecies of S. gallolyticus causing the infection. Here, we present the complete genomes of S. gallolyticus ATCC 43143 (biotype I) and S. pasteurianus ATCC 43144 (biotype II.2). The genomic differences between the two biotypes were characterized with comparative genomic analyses. The chromosome of ATCC 43143 and ATCC 43144 are 2,36 and 2,10 Mb in length and encode 2246 and 1869 CDS respectively. The organization and genomic contents of both genomes were most similar to the recently published S. gallolyticus UCN34, where 2073 (92%) and 1607 (86%) of the ATCC 43143 and ATCC 43144 CDS were conserved in UCN34 respectively. There are around 600 CDS conserved in all Streptococcus genomes, indicating the Streptococcus genus has a small core-genome (constitute around 30% of total CDS) and substantial evolutionary plasticity. We identified eight and five regions of genome plasticity in ATCC 43143 and ATCC 43144 respectively. Within these regions, several proteins were recognized to contribute to the fitness and virulence of each of the two subspecies. We have also predicted putative cell-surface associated proteins that could play a role in adherence to host tissues, leading to persistent infections causing sub-acute and chronic diseases in humans. This study showed evidence that the S. gallolyticus still possesses genes making it suitable in a rumen environment, whereas the ability for S. pasteurianus to live in rumen is reduced. The genome heterogeneity and genetic diversity among the two biotypes, especially membrane and lipoproteins, most likely contribute to the differences in the pathogenesis of the two S. gallolyticus biotypes and the type of disease an infected patient eventually develops

The epidemiology of enterococci

The enterococci are emerging as a significant cause of nosocomial infections, accounting for approximately 10 % of hospital acquired infections. They are found as normal inhabitants of the human gastrointestinal tract, but may also colonize the oropharynx, vagina, perineal region and soft tissue wounds of asymtomatic patients. Until recently, evidence indicated that most enterococcal infections arose from patients' own endogenous flora. Recent studies, however, suggest that exogeneous acquisition may occur and that person-to-person spread, probably on the hands of medical personnel, may be a significant mode of transmission of resistant enterococci within the hospital. The use of broad-spectrum antibiotics, especially cephalosporins, is another major factor in the increasing incidence of enterococcal infections. These findings suggest that barrier precautions, as applied with other resistant nosocomial pathogens, along with more judicial use of antibiotics may be beneficial in preventing nosocomial spread of resistant enterococci.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47899/1/10096_2005_Article_BF01963631.pd

Gender & Sex in Methods and Measurement - Tool 1: Determining and Communicating Eligibility

As part of research, we develop guidelines about who can and who cannot participate in our studies based on shared characteristics called eligibility criteria or inclusionary criteria. This tool is focused on determining and communicating eligibility criteria in ways that are attentive to the lives of people of marginalized and minoritized sexes and genders, which includes but is not limited to intersex, trans, nonbinary and Two-Spirit people

Gender & Sex in Methods and Measurement - Tool 2: Effective Recruitment Strategies

Once we have determined who will be eligible for our research studies, we need to develop a recruitment strategy – a clear plan for identifying and reaching prospective participants, providing them with information about the study, and enrolling them into it. This tool will explore considerations to take into account when recruiting people who are marginalized and minoritized based on their genders, sexes and sexualities

Gender & Sex in Methods and Measurement - Tool 3: Sampling Plans and Data Analyses

When we recruit participants to our research studies, they become a part of our sample – the group of people we will collect data from, or who we will generate data with, to answer our research questions or test our hypotheses. There are several points to consider about sampling in relationship to gender, sex, and sexuality. Here, we offer questions for researchers to ask themselves, issues to carefully consider, and some illustrative example situations

Gender & Sex in Methods and Measurement - Tool 4: Asking About and Measuring Participants' Genders & Sexes

This tool helps researchers understand whether, when and how to ask participants about their genders & sexes. There is no single, correct way to measure people’s genders and sexes, in part because these terms have multiple meanings. This tool serves as a guide to walk researchers through some common approaches to gender and sex measurement with a focus on intentionality, precision and harm reduction

Gender & Sex in Methods and Measurement - Tool 6: Working with Pre-Existing, Secondary and Older Data

Researchers aren’t always working with primary data, they often work with pre-existing, secondary and older data. Sometimes, this means that the data being used was not collected in a way that aligns with recommended practices for measuring gender, sex and sexuality. How should researchers deal with these issues? Tool #6 provides some strategies and tips